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stock bypass valve issue

inzpie

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#1
Hey, I have a stock 2018 fiesta st(besides mounts) with about 120k km on it and recently I'm not hearing the pssst very often anymore when I let off the gas, when I do hear it its while in 3rd or 4th gear and is very quiet/subtle.

I've checked all my connections and hoses, pretty sure there are no leaks, so I'm leaning towards the turbo bypass valve malfunctioning or needs servicing (unless anybody else has another idea of what could be causing this issue.)

Since I can hear it sometimes even though it's now very subtle, I believe it's still 'trying' to do it's job. Does anybody know if I can service/clean/etc this part? I know it's behind my wheel well and is 3 bolts but I haven't gotten to it yet.

Thank you in advance for any advice anybody can offer, and hopefully I posted this on the right place.
 


dhminer

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#2
Hey, I have a stock 2018 fiesta st(besides mounts) with about 120k km on it and recently I'm not hearing the pssst very often anymore when I let off the gas, when I do hear it its while in 3rd or 4th gear and is very quiet/subtle.

I've checked all my connections and hoses, pretty sure there are no leaks, so I'm leaning towards the turbo bypass valve malfunctioning or needs servicing (unless anybody else has another idea of what could be causing this issue.)

Since I can hear it sometimes even though it's now very subtle, I believe it's still 'trying' to do it's job. Does anybody know if I can service/clean/etc this part? I know it's behind my wheel well and is 3 bolts but I haven't gotten to it yet.

Thank you in advance for any advice anybody can offer, and hopefully I posted this on the right place.
Stock bpv is a known leaker. Best bet is to replace it. There are tons of good options out there. Does the car feel down on power like it’s leaking boost? It’s possible it’s stuck closed which isn’t a great thing.
 


OP
I

inzpie

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Thread Starter #3
Stock bpv is a known leaker. Best bet is to replace it. There are tons of good options out there. Does the car feel down on power like it’s leaking boost? It’s possible it’s stuck closed which isn’t a great thing.
Thank you for your response! It doesn't feel lacking power at all, and I've checked all connections besides the connector right on the bpv (haven't been able to get through the wheel well yet due to weather, but should be able to this week).

I suspect you are right and it's either stuck open/closed or somewhere in between, although I do hear it going off quietly once in a while so I believe the actuator is still working but the valve needs servicing. Out of all the things I keep on top of for maintenance like lubing guide pins etc, somehow maintenance for the bpv is one I've missed.

Have been looking at the dv+ and vented dv+, as well as the full drop in with actuator or the HKS bov that replaces the symposer. Truly not sure which I'll go with, but for the moment I'm going to try and clean/oil the stock one just to get it moving and hopefully figure out a replacement that fits my needs in the next month or two. I haven't found much info about servicing the stock one but I assume it's similar to the videos for the dv+ (isopropyl to clean and 5w 20 to oil I believe), providing I don't break what seem like fragile clips on the stock bpv and end up needing to make the decision for a replacement immediately.
 


dhminer

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#4
Thank you for your response! It doesn't feel lacking power at all, and I've checked all connections besides the connector right on the bpv (haven't been able to get through the wheel well yet due to weather, but should be able to this week).

I suspect you are right and it's either stuck open/closed or somewhere in between, although I do hear it going off quietly once in a while so I believe the actuator is still working but the valve needs servicing. Out of all the things I keep on top of for maintenance like lubing guide pins etc, somehow maintenance for the bpv is one I've missed.

Have been looking at the dv+ and vented dv+, as well as the full drop in with actuator or the HKS bov that replaces the symposer. Truly not sure which I'll go with, but for the moment I'm going to try and clean/oil the stock one just to get it moving and hopefully figure out a replacement that fits my needs in the next month or two. I haven't found much info about servicing the stock one but I assume it's similar to the videos for the dv+ (isopropyl to clean and 5w 20 to oil I believe), providing I don't break what seem like fragile clips on the stock bpv and end up needing to make the decision for a replacement immediately.
I have no idea about servicing the stock one, but I am currently running a symposer port BOV and love it.
 


Forsazh

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#5
I have no idea about servicing the stock one, but I am currently running a symposer port BOV and love it.
I'm looking at getting the symposer port BOV from Woosh with the HKS blow off valve. Do you get a check engine light? I've heard that running a vent to atmosphere BOV can cause a check engine light. I live in an emissions testing state and don't want to deal with that.
 


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#6
As long as ur emissions testing doesn't include a visual you should be ok. CEL will be a P0035 for BPV signal low or implausible something or other. Tuner can get rid of that I believe. I'm also running the HKS SSQV in the symposer location and love it!
 


dhminer

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#7
I'm looking at getting the symposer port BOV from Woosh with the HKS blow off valve. Do you get a check engine light? I've heard that running a vent to atmosphere BOV can cause a check engine light. I live in an emissions testing state and don't want to deal with that.
You can get a turbosmart CEL defender that plugs into the BPV terminal that will be unused when you switch to a mechanical BOV
 


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#8
I thought the CEL defender was discontinued? Link to one? I see a BOV solenoid replacement, but not just the plug with a resistor they used to sell.
 


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